// 向上轉(zhuǎn)型：將子類對(duì)象看做是父類對(duì)象
class A{
    public static void draw(A a){  //A的靜態(tài)方法
        System.out.println("調(diào)用該方法，draw一個(gè)A類的圖像");
    }
}
public  class Parallelogram extends A{
    public static void main(String[] args) {
        Parallelogram b = new Parallelogram();
        draw(b);  //調(diào)用父類A的方法，draw一個(gè)A的子類的圖像
    }
}

// 向上轉(zhuǎn)型
class A{
    public static void draw(A a){  //A的靜態(tài)方法
        System.out.println("調(diào)用該方法，draw一個(gè)A類的圖像");
    }
}
public  class Parallelogram extends A{
    public static void main(String[] args) {
        A a = new Parallelogram();             //將子類對(duì)象看作是父類對(duì)象進(jìn)行創(chuàng)建
//        Parallelogram c =  a;                 //不能父類的對(duì)象直接被賦值給子類  會(huì)報(bào)錯(cuò)
        Parallelogram c = (Parallelogram) a;  // 將父類對(duì)象通過顯示類型轉(zhuǎn)換為子類后，可被賦值給子類的對(duì)象
        draw(c);
    }
}

public class Test {
    public static void main(String[] args) {
        A a1 = new A1();
        a1.Eat("a1","ffa1");
        A1 aa1 = (A1)a1;
        aa1.Eat("aa1","ffaa1");

    }
}

class A{
    public  void Eat (String nm,String ffa){
        System.out.println(nm+":方法為"+ffa);
    }
}

class A1 extends A{
}

        /*
        a1:方法為ffa1
        aa1:方法為ffaa1
*/

public class Test {
    public static void main(String[] args) {
        A a1 = new A1();
        a1.Eat("a1","ffa1");
        if (a1 instanceof A1) {
            System.out.println("a1是A1的實(shí)例");
            A1 aa1 = (A1)a1;
            aa1.Eat("aa1","ffaa1");
        }else{
            System.out.println("a1不是A1的實(shí)例");
        }


    }
}

class A{
    public  void Eat (String nm,String ffa){
        System.out.println(nm+":方法為"+ffa);
    }
}

class A1 extends A{
}

        /*
        a1:方法為ffa1
        a1是A1的實(shí)例
        aa1:方法為ffaa1
*/